False Vacuum in the Supersymmetric Mass Varying Neutrinos Model

We present detailed analyses of the vacuum structure of the scalar potential in a supersymmetric Mass Varying Neutrinos model. The observed dark energy density is identified with false vacuum energy and the dark energy scale of order $(10^{-3}eV)^4$ is understood by gravitationally suppressed supersymmetry breaking scale, $F({TeV})^2/M_{Pl}$, in the model. The vacuum expectation values of sneutrinos should be tiny in order that the model works. Some decay processes of superparticles into acceleron and sterile neutrino are also discussed in the model.Comment: 7 pages, 5 figures, revtex, typos correcte

Neutrino masses and mixing from S4 flavor twisting

We discuss a neutrino mass model based on the S4 discrete symmetry where the symmetry breaking is triggered by the boundary conditions of the bulk right-handed neutrino in the fifth spacial dimension. While the symmetry restricts bare mass parameters to flavor-diagonal forms, the viable mixing angles emerge from the wave functions of the Kaluza-Klein modes which carry symmetry breaking effect. The magnitudes of the lepton mixing angles, especially the reactor angle is related to the neutrino mass patterns and the model will be tested in future neutrino experiments, e.g., an early (late) discovery of the reactor angle favors the normal (inverted) hierarchy. The size of extra dimension has a connection to the possible mass spectrum; a small (large) volume corresponds to the normal (inverted) mass hierarchy.Comment: 22 pages, 3 figures; added references for section

Speed of Sound in the Mass Varying Neutrinos Scenario

We discuss about the speed of sound squared in the Mass Varying Neutrinos scenario (MaVaNs). Recently, it was argued that the MaVaNs has a catastrophic instability which is the emergence of an imaginary speed of sound at the non-relativistic limit of neutrinos. As the result of this instability, the neutrino-acceleron fluid cannot act as the dark energy. However, it is found that the speed of sound squared in the neutrino-acceleron fluid could be positive in our model. We examine the speed of sound in two cases of the scalar potential. One is the small fractional power-law potential and another is the logarithmic one. The power-law potential model with the right-handed neutrinos gives a stable one.Comment: 17 pages, References added, minor modification

Embedding the Texture of the Neutrino Mass Matrix into the MaVaNs Scenario

We have embedded the texture of the neutrino mass matrix with three families into the MaVaNs scenario. We take the power-law potential of the acceleron field and a typical texture of active neutrinos, which is derived by the D_4 symmetry and predicts the maximal mixing of the atmospheric neutrino and the vanishing U_{e3}. The effect of couplings among the dark fermion and active neutrinos are studied by putting the current cosmological data and the terrestrial neutrino experimental data. It is found that the neutrino flavor mixings evolve as well as the neutrino masses. Especially, U_{e3} develops into the non-vanishing one and \theta_{atm} deviates from the maximal mixing due to couplings among the dark fermion and active neutrinos.Comment: Sections 3 and 4 are changed and one table is added. 16pages and 2 figure

Hybrid Textures of Neutrinos

We present numerical and comprehensive analyses of the sixty hybrid textures of neutrinos, which have an equality of matrix elements and one zero. These textures are possibly derived from the discrete symmetry. Only six textures among sixty ones are excluded by the present experimental data. Since there are many textures which give similar predictions, the textures are classified based on the numerical results. The neutrinoless double beta decay is also examined in these textures. Our results suggest that there remain still rich structures of the neutrino mass matrix in the phenomenological point of view.Comment: 19 pages, 9 figures; analytical discussions added, table and reference adde

Análisis descriptivo del proceso de implementación del nivel 2 del modelo CMMI en una empresa regional de desarrollo de software

CMMI (Capability Maturity Model Integration) is basically a continu­ous-improvement inspired model to classify software development organizations according to a five-level maturity and capability scale. The classification in a given level is based on the dominance that an organization shows evidence to have over the areas of that level, which in turn reflects the degree of maturity of the organization and of the processes that it follows to develop software. This article presents a preliminary descriptive analysis of a level 2 implementation process of the CMMI model in a Colombian software devel­opment company, making an overall presentation of how it was brought into practice the theory of the model in the processes of the company, to be compliant with the conditions, goals and practices defined in the level 2 process areas of the model. The arti­cle also describes the problems which arose in the execution of the project, as well as how they were solved. As preliminary results are presented some of the indicators defined by the company for the software processes, and the software tools that were ac­quired or developed for the support of the implementation of the process areas. Finally, some conclusions and recommendations which can be found of use and application are given for similar projects.El Modelo de Capacidad y Madurez (Capability Maturity Model Integration, CMMI), es un modelo inspirado en el mejoramiento continuo que permite clasificar a las organizaciones de desarrollo de software según una escala de cinco niveles de madurez y capacidad. La clasificación en un determinado nivel se realiza sobre la base del dominio que una organización evidencia tener acerca de las áreas de proceso de dicho nivel, lo cual a su vez refleja el grado de madurez de la misma y de los procesos que ella realiza para desarrollar software. En este artículo se presenta un análisis descriptivo preliminar del proceso de implementación del nivel 2 del modelo CMMI en una empresa regional de desarrollo de software, exponiendo de manera general cómo se realizó la aplicación de la teoría del modelo en los procesos requeridos para cumplir con las condiciones, metas y prácticas de las áreas de proceso del nivel 2 del modelo, así como los problemas e inconvenientes presentados en la ejecución del proyecto, junto con sus respectivas soluciones. A modo de resultados preliminares, se presentan algunos de los indicadores definidos por la empresa para esos procesos, las herramientas de apoyo que se adquirieron o desarrollaron para la implementación de las áreas de proceso. Finalmente, se dan algunas conclusiones y recomendaciones de aplicación que pueden ser útiles para proyectos similares

Soft supersymmetry breaking terms from A4 lepton flavor symmetry

We study the supersymmetric model with the A4 lepton flavor symmetry, in particular soft supersymmetry breaking terms, which are predicted from the A4 lepton flavor symmetry. We evaluate soft slepton masses and A-terms within the framework of supergravity theory. Constraints due to experiments of flavor changing neutral current processes are examined.Comment: minor modification, 17page

Prediction of Ue3U_{e3} in Neutrino Mass Matrix with Two Zeros

We have discussed predictions of $|U_{e3}|$ and $J_{CP}$ in the framework of the neutrino mass matrix with two zeros. In the case of the best fit values of $\tan^2\theta_{12}$, $\tan^2\theta_{23}$, $\Delta m^2_{\rm sun}$ and $\Delta m_{\rm atm}^2$, the prediction of $|U_{e3}|$ is $0.11\sim 0.14$. The lower bound of $|U_{e3}|$ is 0.05, which depends on $\tan\theta_{12}$ and $\tan\theta_{23}$. We have investigated the stability of these predictions taking account of small corrections to zeros, which may come from radiative corrections or off-diagonal elements of the charged lepton massmatrix. The lower bound of $|U_{e3}|$ comes down considerably due to the small corrections to zeros.Comment: Figures and discussions are adde

Neutrino mass matrix with U(2) flavor symmetry and neutrino oscillations

The three neutrino mass matrices in the $SU(5)\times U(2)$ model are studied focusing on the neutrino oscillation experiments. The atmospheric neutrino anomaly could be explained by the large $\nu_{\mu} - \nu_{\tau}$ oscillation. The long baseline experiments are expected to detect signatures of the neutrino oscillation even if the atmospheric neutrino anomaly is not due to the neutrino oscillation. However, the model cannot solve the solar neutrino deficit while it could be reconciled with the LSND data.Comment: 12 pages, LaTex file, to be published in PR

Carcinoma de paratiróide: características clínicas e anátomo-patológicas de cinco casos

Parathyroid carcinoma is a rare disease, with about 535 cases reported in the literature until now. In this paper, we reviewed 5 cases of parathyroid carcinoma followed at Universidade Federal de São Paulo (UNIFESP) from 1983 to 1998, and discuss aspects of clinical presentation, diagnosis and treatment. Four patients were female and 1 male, with median ages of 52 years (10 to 77 years). Initial clinical complains were bone pain and weight loss in 4 patients, traumatic fracture in 2, and fracture without trauma in 3. Kidney stone was present in 1 patient. All had a palpable mass in the cervical region and presented with high calcium levels: 14.9±1.7mg/dL (mean±SD). Parathyroid hormone (PTH) levels were extremely high, showing the severity of the disease. All patients had surgical exploration where a tumor mass was recognized and removed. Pathologic examination demonstrated parathyroid carcinoma in all. On follow-up, 2 patients had recurrence and died due to complications of hyperparathyroidism. To date, the other 3 patients have no evidences of recurrence.O carcinoma de paratiróide é uma entidade rara, havendo cerca de 535 casos descritos na literatura. Neste trabalho, revisamos a nossa casuística de 5 pacientes com carcinoma de paratiróide avaliados no período de 1983 a 1998 no serviço de Doenças Ósteo-Metabólicas da Universidade Federal de São Paulo (UNIFESP), analisando critérios diagnósticos, conduta terapêutica e a evolução destes pacientes e comparando os nossos dados com os achados de literatura. Entre os nossos pacientes, 4 eram do sexo feminino e 1 do sexo masculino, com mediana ao diagnóstico de 52 anos de idade, variando de 10 a 77 anos. As queixas iniciais incluíam presença de dores ósseas acompanhada de perda de peso em 4 pacientes, presença de fratura não traumática em 3 pacientes e traumática em 2 e clínica de nefrolitíase em 1 paciente. Todos apresentavam nódulo palpável em região cervical, níveis de cálcio total bastante elevados com média(±DP) de 14,9±1,7mg/dL. PTH também se encontrava muito elevado, refletindo a magnitude da severidade da doença. Todos foram submetidos à exploração cirúrgica cervical com retirada da massa tumoral, que foi coincidente com o achado palpatório de nódulo cervical. O exame anátomo-patológico revelou o diagnóstico de carcinoma de paratiróide em todos estes casos. No seguimento, 2 pacientes apresentaram recidiva tumoral e evoluíram para óbito por complicações do hiperparatiroidismo. Os outros 3 casos encontram-se em acompanhamento ambulatorial no nosso hospital, sem evidências até o momento de recidiva tumoral.Universidade Federal de São Paulo (UNIFESP) Disciplina de Endocrinologia e MetabologiaUniversidade Federal de São Paulo (UNIFESP) Disciplina de Anatomia PatológicaUniversidade Federal de São Paulo (UNIFESP) Disciplina de Cirurgia de Cabeça e PescoUNIFESP, Disciplina de Endocrinologia e MetabologiaUNIFESP, Disciplina de Anatomia PatológicaUNIFESP, Disciplina de Cirurgia de Cabeça e PescoSciEL